/* $NetBSD: dir.c,v 1.28 2013/06/23 07:28:36 dholland Exp $ */ /* * Copyright (c) 1980, 1986, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Copyright (c) 1997 Manuel Bouyer. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #ifndef lint #if 0 static char sccsid[] = "@(#)dir.c 8.5 (Berkeley) 12/8/94"; #else __RCSID("$NetBSD: dir.c,v 1.28 2013/06/23 07:28:36 dholland Exp $"); #endif #endif /* not lint */ #include #include #include #include #include #include #include /* for IFMT & friends */ #include #include #include #include #include "fsck.h" #include "fsutil.h" #include "extern.h" const char *lfname = "lost+found"; int lfmode = 01700; struct ext2fs_dirtemplate emptydir = { .dot_ino = 0, .dot_reclen = UFS_DIRBLKSIZ, }; struct ext2fs_dirtemplate dirhead = { .dot_ino = 0, .dot_reclen = 12, .dot_namlen = 1, .dot_type = EXT2_FT_DIR, .dot_name = ".", .dotdot_ino = 0, .dotdot_reclen = UFS_DIRBLKSIZ - 12, .dotdot_namlen = 2, .dotdot_type = EXT2_FT_DIR, .dotdot_name = "..", }; #undef UFS_DIRBLKSIZ static int expanddir(struct ext2fs_dinode *, char *); static void freedir(ino_t, ino_t); static struct ext2fs_direct *fsck_readdir(struct inodesc *); static struct bufarea *getdirblk(daddr_t, long); static int lftempname(char *, ino_t); static int mkentry(struct inodesc *); static int chgino(struct inodesc *); /* * Propagate connected state through the tree. */ void propagate(void) { struct inoinfo **inpp, *inp, *pinp; struct inoinfo **inpend; /* * Create a list of children for each directory. */ inpend = &inpsort[inplast]; for (inpp = inpsort; inpp < inpend; inpp++) { inp = *inpp; if (inp->i_parent == 0 || inp->i_number == EXT2_ROOTINO) continue; pinp = getinoinfo(inp->i_parent); inp->i_parentp = pinp; inp->i_sibling = pinp->i_child; pinp->i_child = inp; } inp = getinoinfo(EXT2_ROOTINO); while (inp) { statemap[inp->i_number] = DFOUND; if (inp->i_child && statemap[inp->i_child->i_number] == DSTATE) inp = inp->i_child; else if (inp->i_sibling) inp = inp->i_sibling; else inp = inp->i_parentp; } } /* * Scan each entry in a directory block. */ int dirscan(struct inodesc *idesc) { struct ext2fs_direct *dp; struct bufarea *bp; int dsize, n; long blksiz; char *dbuf = NULL; if ((dbuf = malloc(sblock.e2fs_bsize)) == NULL) err(8, "Can't allocate directory block"); if (idesc->id_type != DATA) errexit("wrong type to dirscan %d", idesc->id_type); if (idesc->id_entryno == 0 && (idesc->id_filesize & (sblock.e2fs_bsize - 1)) != 0) idesc->id_filesize = roundup(idesc->id_filesize, sblock.e2fs_bsize); blksiz = idesc->id_numfrags * sblock.e2fs_bsize; if (chkrange(idesc->id_blkno, idesc->id_numfrags)) { idesc->id_filesize -= blksiz; free(dbuf); return (SKIP); } idesc->id_loc = 0; for (dp = fsck_readdir(idesc); dp != NULL; dp = fsck_readdir(idesc)) { dsize = fs2h16(dp->e2d_reclen); memcpy(dbuf, dp, (size_t)dsize); idesc->id_dirp = (struct ext2fs_direct *)dbuf; if ((n = (*idesc->id_func)(idesc)) & ALTERED) { bp = getdirblk(idesc->id_blkno, blksiz); memcpy(bp->b_un.b_buf + idesc->id_loc - dsize, dbuf, (size_t)dsize); dirty(bp); sbdirty(); } if (n & STOP) { free(dbuf); return (n); } } free(dbuf); return (idesc->id_filesize > 0 ? KEEPON : STOP); } /* * get next entry in a directory. */ static struct ext2fs_direct * fsck_readdir(struct inodesc *idesc) { struct ext2fs_direct *dp, *ndp; struct bufarea *bp; long size, blksiz, fix, dploc; blksiz = idesc->id_numfrags * sblock.e2fs_bsize; bp = getdirblk(idesc->id_blkno, blksiz); if (idesc->id_loc % sblock.e2fs_bsize == 0 && idesc->id_filesize > 0 && idesc->id_loc < blksiz) { dp = (struct ext2fs_direct *)(bp->b_un.b_buf + idesc->id_loc); if (dircheck(idesc, dp)) goto dpok; if (idesc->id_fix == IGNORE) return (0); fix = dofix(idesc, "DIRECTORY CORRUPTED"); bp = getdirblk(idesc->id_blkno, blksiz); dp = (struct ext2fs_direct *)(bp->b_un.b_buf + idesc->id_loc); dp->e2d_reclen = h2fs16(sblock.e2fs_bsize); dp->e2d_ino = 0; dp->e2d_namlen = 0; dp->e2d_type = 0; dp->e2d_name[0] = '\0'; if (fix) dirty(bp); idesc->id_loc += sblock.e2fs_bsize; idesc->id_filesize -= sblock.e2fs_bsize; return (dp); } dpok: if (idesc->id_filesize <= 0 || idesc->id_loc >= blksiz) return NULL; dploc = idesc->id_loc; dp = (struct ext2fs_direct *)(bp->b_un.b_buf + dploc); idesc->id_loc += fs2h16(dp->e2d_reclen); idesc->id_filesize -= fs2h16(dp->e2d_reclen); if ((idesc->id_loc % sblock.e2fs_bsize) == 0) return (dp); ndp = (struct ext2fs_direct *)(bp->b_un.b_buf + idesc->id_loc); if (idesc->id_loc < blksiz && idesc->id_filesize > 0 && dircheck(idesc, ndp) == 0) { size = sblock.e2fs_bsize - (idesc->id_loc % sblock.e2fs_bsize); idesc->id_loc += size; idesc->id_filesize -= size; if (idesc->id_fix == IGNORE) return (0); fix = dofix(idesc, "DIRECTORY CORRUPTED"); bp = getdirblk(idesc->id_blkno, blksiz); dp = (struct ext2fs_direct *)(bp->b_un.b_buf + dploc); dp->e2d_reclen = h2fs16(fs2h16(dp->e2d_reclen) + size); if (fix) dirty(bp); } return (dp); } /* * Verify that a directory entry is valid. * This is a superset of the checks made in the kernel. */ int dircheck(struct inodesc *idesc, struct ext2fs_direct *dp) { int size; char *cp; int spaceleft; u_int16_t reclen = fs2h16(dp->e2d_reclen); spaceleft = sblock.e2fs_bsize - (idesc->id_loc % sblock.e2fs_bsize); if (fs2h32(dp->e2d_ino) > maxino || reclen == 0 || reclen > spaceleft || (reclen & 0x3) != 0) return (0); if (dp->e2d_ino == 0) return (1); if (sblock.e2fs.e2fs_rev < E2FS_REV1 || (sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE) == 0) if (dp->e2d_type != 0) return (1); size = EXT2FS_DIRSIZ(dp->e2d_namlen); if (reclen < size || idesc->id_filesize < size /* || dp->e2d_namlen > EXT2FS_MAXNAMLEN */) return (0); for (cp = dp->e2d_name, size = 0; size < dp->e2d_namlen; size++) if (*cp == '\0' || (*cp++ == '/')) return (0); return (1); } void direrror(ino_t ino, const char *errmesg) { fileerror(ino, ino, errmesg); } void fileerror(ino_t cwd, ino_t ino, const char *errmesg) { struct ext2fs_dinode *dp; char pathbuf[MAXPATHLEN + 1]; pwarn("%s ", errmesg); pinode(ino); printf("\n"); getpathname(pathbuf, sizeof(pathbuf), cwd, ino); if ((ino < EXT2_FIRSTINO && ino != EXT2_ROOTINO) || ino > maxino) { pfatal("NAME=%s\n", pathbuf); return; } dp = ginode(ino); if (ftypeok(dp)) pfatal("%s=%s\n", (fs2h16(dp->e2di_mode) & IFMT) == IFDIR ? "DIR" : "FILE", pathbuf); else pfatal("NAME=%s\n", pathbuf); } void adjust(struct inodesc *idesc, short lcnt) { struct ext2fs_dinode *dp; dp = ginode(idesc->id_number); if (fs2h16(dp->e2di_nlink) == lcnt) { if (linkup(idesc->id_number, (ino_t)0) == 0) clri(idesc, "UNREF", 0); } else { pwarn("LINK COUNT %s", (lfdir == idesc->id_number) ? lfname : ((fs2h16(dp->e2di_mode) & IFMT) == IFDIR ? "DIR" : "FILE")); pinode(idesc->id_number); printf(" COUNT %d SHOULD BE %d", fs2h16(dp->e2di_nlink), fs2h16(dp->e2di_nlink) - lcnt); if (preen) { if (lcnt < 0) { printf("\n"); pfatal("LINK COUNT INCREASING"); } printf(" (ADJUSTED)\n"); } if (preen || reply("ADJUST") == 1) { dp->e2di_nlink = h2fs16(fs2h16(dp->e2di_nlink) - lcnt); inodirty(); } } } static int mkentry(struct inodesc *idesc) { struct ext2fs_direct *dirp = idesc->id_dirp; struct ext2fs_direct newent; int newlen, oldlen; newent.e2d_type = 0; /* XXX gcc */ newent.e2d_namlen = strlen(idesc->id_name); if (sblock.e2fs.e2fs_rev > E2FS_REV0 && (sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE)) newent.e2d_type = inot2ext2dt(typemap[idesc->id_parent]); newlen = EXT2FS_DIRSIZ(newent.e2d_namlen); if (dirp->e2d_ino != 0) oldlen = EXT2FS_DIRSIZ(dirp->e2d_namlen); else oldlen = 0; if (fs2h16(dirp->e2d_reclen) - oldlen < newlen) return (KEEPON); newent.e2d_reclen = h2fs16(fs2h16(dirp->e2d_reclen) - oldlen); dirp->e2d_reclen = h2fs16(oldlen); dirp = (struct ext2fs_direct *)(((char *)dirp) + oldlen); dirp->e2d_ino = h2fs32(idesc->id_parent); /* ino to be entered is in id_parent */ dirp->e2d_reclen = newent.e2d_reclen; dirp->e2d_namlen = newent.e2d_namlen; dirp->e2d_type = newent.e2d_type; memcpy(dirp->e2d_name, idesc->id_name, (size_t)(dirp->e2d_namlen)); return (ALTERED|STOP); } static int chgino(struct inodesc *idesc) { struct ext2fs_direct *dirp = idesc->id_dirp; u_int16_t namlen = dirp->e2d_namlen; if (strlen(idesc->id_name) != namlen || strncmp(dirp->e2d_name, idesc->id_name, (int)namlen)) return (KEEPON); dirp->e2d_ino = h2fs32(idesc->id_parent); if (sblock.e2fs.e2fs_rev > E2FS_REV0 && (sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE)) dirp->e2d_type = inot2ext2dt(typemap[idesc->id_parent]); else dirp->e2d_type = 0; return (ALTERED|STOP); } int linkup(ino_t orphan, ino_t parentdir) { struct ext2fs_dinode *dp; int lostdir; ino_t oldlfdir; struct inodesc idesc; char tempname[BUFSIZ]; memset(&idesc, 0, sizeof(struct inodesc)); dp = ginode(orphan); lostdir = (fs2h16(dp->e2di_mode) & IFMT) == IFDIR; pwarn("UNREF %s ", lostdir ? "DIR" : "FILE"); pinode(orphan); if (preen && inosize(dp) == 0) return (0); if (preen) printf(" (RECONNECTED)\n"); else if (reply("RECONNECT") == 0) return (0); if (lfdir == 0) { dp = ginode(EXT2_ROOTINO); idesc.id_name = lfname; idesc.id_type = DATA; idesc.id_func = findino; idesc.id_number = EXT2_ROOTINO; if ((ckinode(dp, &idesc) & FOUND) != 0) { lfdir = idesc.id_parent; } else { pwarn("NO lost+found DIRECTORY"); if (preen || reply("CREATE")) { lfdir = allocdir(EXT2_ROOTINO, (ino_t)0, lfmode); if (lfdir != 0) { if (makeentry(EXT2_ROOTINO, lfdir, lfname) != 0) { if (preen) printf(" (CREATED)\n"); } else { freedir(lfdir, EXT2_ROOTINO); lfdir = 0; if (preen) printf("\n"); } } } } if (lfdir == 0) { pfatal("SORRY. CANNOT CREATE lost+found DIRECTORY"); printf("\n\n"); return (0); } } dp = ginode(lfdir); if ((fs2h16(dp->e2di_mode) & IFMT) != IFDIR) { pfatal("lost+found IS NOT A DIRECTORY"); if (reply("REALLOCATE") == 0) return (0); oldlfdir = lfdir; if ((lfdir = allocdir(EXT2_ROOTINO, (ino_t)0, lfmode)) == 0) { pfatal("SORRY. CANNOT CREATE lost+found DIRECTORY\n\n"); return (0); } if ((changeino(EXT2_ROOTINO, lfname, lfdir) & ALTERED) == 0) { pfatal("SORRY. CANNOT CREATE lost+found DIRECTORY\n\n"); return (0); } inodirty(); idesc.id_type = ADDR; idesc.id_func = pass4check; idesc.id_number = oldlfdir; adjust(&idesc, lncntp[oldlfdir] + 1); lncntp[oldlfdir] = 0; dp = ginode(lfdir); } if (statemap[lfdir] != DFOUND) { pfatal("SORRY. NO lost+found DIRECTORY\n\n"); return (0); } (void)lftempname(tempname, orphan); if (makeentry(lfdir, orphan, tempname) == 0) { pfatal("SORRY. NO SPACE IN lost+found DIRECTORY"); printf("\n\n"); return (0); } lncntp[orphan]--; if (lostdir) { if ((changeino(orphan, "..", lfdir) & ALTERED) == 0 && parentdir != (ino_t)-1) (void)makeentry(orphan, lfdir, ".."); dp = ginode(lfdir); dp->e2di_nlink = h2fs16(fs2h16(dp->e2di_nlink) +1); inodirty(); lncntp[lfdir]++; pwarn("DIR I=%llu CONNECTED. ", (unsigned long long)orphan); if (parentdir != (ino_t)-1) printf("PARENT WAS I=%llu\n", (unsigned long long)parentdir); if (preen == 0) printf("\n"); } return (1); } /* * fix an entry in a directory. */ int changeino(ino_t dir, const char *name, ino_t newnum) { struct inodesc idesc; memset(&idesc, 0, sizeof(struct inodesc)); idesc.id_type = DATA; idesc.id_func = chgino; idesc.id_number = dir; idesc.id_fix = DONTKNOW; idesc.id_name = name; idesc.id_parent = newnum; /* new value for name */ return (ckinode(ginode(dir), &idesc)); } /* * make an entry in a directory */ int makeentry(ino_t parent, ino_t ino, const char *name) { struct ext2fs_dinode *dp; struct inodesc idesc; char pathbuf[MAXPATHLEN + 1]; if ((parent < EXT2_FIRSTINO && parent != EXT2_ROOTINO) || parent >= maxino || (ino < EXT2_FIRSTINO && ino < EXT2_ROOTINO) || ino >= maxino) return (0); memset(&idesc, 0, sizeof(struct inodesc)); idesc.id_type = DATA; idesc.id_func = mkentry; idesc.id_number = parent; idesc.id_parent = ino; /* this is the inode to enter */ idesc.id_fix = DONTKNOW; idesc.id_name = name; dp = ginode(parent); if (inosize(dp) % sblock.e2fs_bsize) { inossize(dp, roundup(inosize(dp), sblock.e2fs_bsize)); inodirty(); } if ((ckinode(dp, &idesc) & ALTERED) != 0) return (1); getpathname(pathbuf, sizeof(pathbuf), parent, parent); dp = ginode(parent); if (expanddir(dp, pathbuf) == 0) return (0); return (ckinode(dp, &idesc) & ALTERED); } /* * Attempt to expand the size of a directory */ static int expanddir(struct ext2fs_dinode *dp, char *name) { daddr_t lastbn, newblk; struct bufarea *bp; char *firstblk; lastbn = ext2_lblkno(&sblock, inosize(dp)); if (lastbn >= EXT2FS_NDADDR - 1 || fs2h32(dp->e2di_blocks[lastbn]) == 0 || inosize(dp) == 0) { return (0); } if ((newblk = allocblk()) == 0) { return (0); } dp->e2di_blocks[lastbn + 1] = dp->e2di_blocks[lastbn]; dp->e2di_blocks[lastbn] = h2fs32(newblk); inossize(dp, inosize(dp) + sblock.e2fs_bsize); inosnblock(dp, inonblock(dp) + btodb(sblock.e2fs_bsize)); bp = getdirblk(fs2h32(dp->e2di_blocks[lastbn + 1]), sblock.e2fs_bsize); if (bp->b_errs) goto bad; if ((firstblk = malloc(sblock.e2fs_bsize)) == NULL) err(8, "cannot allocate first block"); memcpy(firstblk, bp->b_un.b_buf, sblock.e2fs_bsize); bp = getdirblk(newblk, sblock.e2fs_bsize); if (bp->b_errs) { free(firstblk); goto bad; } memcpy(bp->b_un.b_buf, firstblk, sblock.e2fs_bsize); free(firstblk); dirty(bp); bp = getdirblk(fs2h32(dp->e2di_blocks[lastbn + 1]), sblock.e2fs_bsize); if (bp->b_errs) goto bad; emptydir.dot_reclen = h2fs16(sblock.e2fs_bsize); memcpy(bp->b_un.b_buf, &emptydir, sizeof emptydir); pwarn("NO SPACE LEFT IN %s", name); if (preen) printf(" (EXPANDED)\n"); else if (reply("EXPAND") == 0) goto bad; dirty(bp); inodirty(); return (1); bad: dp->e2di_blocks[lastbn] = dp->e2di_blocks[lastbn + 1]; dp->e2di_blocks[lastbn + 1] = 0; inossize(dp, inosize(dp) - sblock.e2fs_bsize); inosnblock(dp, inonblock(dp) - btodb(sblock.e2fs_bsize)); freeblk(newblk); return (0); } /* * allocate a new directory */ int allocdir(ino_t parent, ino_t request, int mode) { ino_t ino; struct ext2fs_dinode *dp; struct bufarea *bp; struct ext2fs_dirtemplate *dirp; ino = allocino(request, IFDIR|mode); dirhead.dot_reclen = h2fs16(12); /* XXX */ dirhead.dotdot_reclen = h2fs16(sblock.e2fs_bsize - 12); /* XXX */ dirhead.dot_namlen = 1; if (sblock.e2fs.e2fs_rev > E2FS_REV0 && (sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE)) dirhead.dot_type = EXT2_FT_DIR; else dirhead.dot_type = 0; dirhead.dotdot_namlen = 2; if (sblock.e2fs.e2fs_rev > E2FS_REV0 && (sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE)) dirhead.dotdot_type = EXT2_FT_DIR; else dirhead.dotdot_type = 0; dirp = &dirhead; dirp->dot_ino = h2fs32(ino); dirp->dotdot_ino = h2fs32(parent); dp = ginode(ino); bp = getdirblk(fs2h32(dp->e2di_blocks[0]), sblock.e2fs_bsize); if (bp->b_errs) { freeino(ino); return (0); } memcpy(bp->b_un.b_buf, dirp, sizeof(struct ext2fs_dirtemplate)); dirty(bp); dp->e2di_nlink = h2fs16(2); inodirty(); if (ino == EXT2_ROOTINO) { lncntp[ino] = fs2h16(dp->e2di_nlink); cacheino(dp, ino); return(ino); } if (statemap[parent] != DSTATE && statemap[parent] != DFOUND) { freeino(ino); return (0); } cacheino(dp, ino); statemap[ino] = statemap[parent]; if (statemap[ino] == DSTATE) { lncntp[ino] = fs2h16(dp->e2di_nlink); lncntp[parent]++; } dp = ginode(parent); dp->e2di_nlink = h2fs16(fs2h16(dp->e2di_nlink) + 1); inodirty(); return (ino); } /* * free a directory inode */ static void freedir(ino_t ino, ino_t parent) { struct ext2fs_dinode *dp; if (ino != parent) { dp = ginode(parent); dp->e2di_nlink = h2fs16(fs2h16(dp->e2di_nlink) - 1); inodirty(); } freeino(ino); } /* * generate a temporary name for the lost+found directory. */ static int lftempname(char *bufp, ino_t ino) { ino_t in; char *cp; int namlen; cp = bufp + 2; for (in = maxino; in > 0; in /= 10) cp++; *--cp = 0; namlen = cp - bufp; in = ino; while (cp > bufp) { *--cp = (in % 10) + '0'; in /= 10; } *cp = '#'; return (namlen); } /* * Get a directory block. * Insure that it is held until another is requested. */ static struct bufarea * getdirblk(daddr_t blkno, long size) { if (pdirbp != 0) pdirbp->b_flags &= ~B_INUSE; pdirbp = getdatablk(blkno, size); return (pdirbp); }